Transparent electrodes having optical transmittance and electroconductivity are used for flat panel display devices or light-emitting diode (LED) devices. Methods of forming a thin film to form such transparent electrodes have already been studied and commercially available. For example, transparent electrodes formed by depositing indium tin oxide (ITO) on a glass substrate have higher electroconductivity than when a conventional metal oxide is used, and accordingly, they are already commercially available for use as a transparent, electroconductive thin film electrode.
However, indium tin oxide (ITO) manufactured according to such a commercially available method needs to be deposited at high temperature. The high-temperature deposition and the need for indium result in high manufacturing costs. Also, due to its fragile properties, it is difficult to embody flexible electronic devices and select various materials to embody photoelectronic devices.
There have been efforts to use a roll-to-roll method to manufacture of flexible displays at low costs and in great quantities. To this end, flexible electrodes are required. In addition, a transparent electrode is required to have anisotropic and electroconductive properties to be suitable for fine pitch.